The present invention relates generally to portable data collector and analyzer systems for collecting and analyzing data and, in particular, to a handheld portable data collector and analyzer apparatus and method for collecting and analyzing industrial plant asset data for protecting and managing industrial plant assets including machinery.
Portable data collector and analyzer apparatus supporting predictive and preventative maintenance of plant assets have been employed in industry for a number of years. However, this apparatus is specialized and can only be targeted for narrow applications. For example, hand-held vibration measuring apparatus has been designed and targeted for the predictive and preventative maintenance of rotating machinery assets. Likewise, compressor performance measuring systems have been designed and targeted for reciprocating compressors. Manual data loggers have been used to record the condition of large assets such as pipe-work and underground tunnels. Further apparatus is required to align and balance machinery. This methodology of employing a large variety of specialized apparatus has resulted in significant costs and logistical problems for maintenance departments and personnel in industrial environments.
For example, the employment of a multiplicity of specialized apparatus for providing predictive and preventative maintenance of industrial plant assets augments costs by having a direct correlation to the amount of training required by personnel on each of the different specialized apparatus.
Additionally, personnel making multiple visits to a site with each of the specialized apparatus or carrying a collection of the specialized apparatus to a site for collecting data is both a laborious and time-consuming task that also augments the costs of providing predictive and preventative maintenance of industrial plant assets.
Furthermore, the task of procuring, maintaining and training personnel on a variety of different apparatus often from a variety of vendors and then routing the personnel with this variety of apparatus for collecting data is a huge logistical problem which is both costly and time consuming and results in resources being directed to the logistical problems of collecting data at the expense of correcting problems.
Moreover, safety risks to the health of maintenance personnel in industrial environments are significant. For example, many installations are classified as hazardous due to the likelihood of the presence of explosive gases. These gases, in even much smaller concentrations, may also be deleterious to the health of maintenance personnel. Thus, the employment of a multiplicity of specialized apparatus for providing predictive and preventative maintenance of industrial plant assets increases the exposure of personnel to these hazards and thus brings about greater safety risks.
Hence, there is a need to provide a single portable data collector and analyzer apparatus that not only provides predictive and preventative maintenance of a multiplicity of commonly occurring assets within an industrial environment for reducing costs, training and logistical problems but also provides an apparatus that increases the types of measurements that can made during each visit to each asset for reducing the exposure and safety risks of personnel to these hazardous environments thereby providing, inter alia, significant costs, training, logistical, safety, and timeliness advantages.
Notwithstanding, current portable data collector and analyzer apparatus have also failed to address the important fact that typically machinery diagnostics rarely rely on a single plot or data type for a complete understanding of problems and in stark contrast one looks for multiple indicators from various sources to confirm problems. Additionally, current portable data collector and analyzer apparatus require significant manual operation which is more prone to human error. Furthermore, there is a need to increase the speed and accuracy in current portable data collector and analyzer apparatus.
In view of the foregoing, there is a need for a single portable data collector and analyzer apparatus that collects and analysis a variety of different types of asset data in a variety of different ways. Additionally, there is also a need for increasing the ease and accuracy in which these instrumentalities operate for, inter alia, providing fast and accurate data collection thereby allowing personnel to correct (rather then detect) problems. Furthermore, the improvement in speed and accuracy directly correlate to cost savings and to the speed in which problems may be addressed.
The present invention recognizes the shortcomings of the known prior art and is distinguished thereover in a multiplicity of ways. One of the starkest differentiations that the present invention enjoys over the known prior art involves the fact that the present invention is not a specialized apparatus that merely targets a single category of machinery or other plant asset for providing predictive and preventative maintenance. In stark contrast, the present invention provides a single handheld multi-purpose portable data collector and analyzer apparatus and method that, inter alia, provides predictive and preventative maintenance of a multiplicity of commonly occurring assets within an industrial environment for reducing costs, training and logistical problems. The single handheld multi-purpose portable data collector and analyzer apparatus and method, in accordance with the present invention, also increases the types of measurements that can made during each visit to each asset for providing significant cost, training, logistical, safety, and timeliness advantages.
Additionally, the present invention combines a flexible hardware and software design to provide a multi-purpose apparatus and method that permits the preventative and predictive maintenance of the multifarious types of assets typically found within an industrial complex. It can be configured to be operatively coupled with a wide range of transducer types e.g. vibration, temperature, speed, process variable, pressure as well as provide the means to manually record a broad range of values and observations relating to the condition of a variety of assets including machines. Moreover, the present invention provides a single multi-purpose apparatus that employs a single unified display application for addressing the wide range of transducer types and signal processing options.
Furthermore, the present invention is designed to provide extensive external communication capabilities. As a result, the present invention is capable of correlating information from multiple sources that allows timely, operational decisions on machinery condition that consider both the machinery and the surrounding process conditions/constraints. Thus, the present invention provides fewer and less severe failures, better production availability, maintenance cost reductions, and the potential for increased production revenues. This ability is provided by the present invention gathering information from multiple information sources within the industrial complex and integrating the information into a single upload to a host computer for further analysis and storage.
For a clear explanation, the present invention can be partitioned into a transducer input/output module, a analog signal conditioning module, an anti-alias filtering and analog to digital converter module, microcontroller module, a digital signal processing module, a user input and display module, a communications module, and a power supply/charger module.
These modules are preferably housed by an injection molded casing formed from a polycarbonate/ABS material for providing high impact resistance and durability.
Transducer Input/Output Transfer Module
The transducer input/output module provides connector means for transferring input and output signals between the analog signal conditioning module and transducers interfaced to the connector means via cables or other signal transmitting medium.
Analog Signal Conditioning Module
The analog signal conditioning module is comprised of two fully functional channels which couple to a wide variety of transducers. Specifically, the two functional channels each provide a pair of constant current sources which can be toggled to power an acceleration or velocity transducer. Each of the two functional channels also include an interface for general purpose signal inputs, including displacement, velocity, acceleration, temperature, pressure and other process variables transducers which produce voltage outputs in the range from a negative 24 to a positive 10 volts. One specific example is the powering of negative 24 volt proximity transducers. The signals outputted by these transducers are conditioned to, for example, a range of about plus 1.25 to plus 3.75 volts and, in turn, are passed to the DSP module.
Additionally, the analog signal conditioning module includes a third channel for phase and speed input. The present invention supports phase reference input from single output devices, such as displacement transducers, optical phase references transducers or magnetic pickup transducers, or from dual output devices, such as encoder transducers. The signals outputted by the single output transducers that are in range of a negative 24 to a positive 10 volts are conditioned to, for example, a range of about 0 to 2.5 volts and are, in turn, passed to the DSP module. The signals outputted by the dual output transducers are pulled up to about 5 volts and are conditioned to, for example, a range of about 3 to 3.3 volts and are, in turn, passed to the DSP module.
Furthermore, the analog signal conditioning module includes a fourth channel for receiving and conditioning input signals from an Auto-Point ID device such as a barcode reader and outputting conditioned signals to the microcontroller module.
Moreover, the analog signal conditioning module includes a self-test mechanism means that can be toggled to disconnect the transducer inputs from each of the two fully functional channels and from the third channel. A know voltage is then applied to each of the respective signal paths and then their outputs are measured and compared against an ideal value via the DSP module for determining whether the signal paths are working correctly or not.
Anti-alias Filtering and Analog to Digital Converter Module
The anti-alias filtering and analog to digital converter module includes a pair of multiplexers which receive signals from the analog signal conditioning module. Each of the multiplexers can select one source from the fully functional channels and the third channel. Each of the outputs from the pair of multiplexers is connected to a separate anti-alias filter which filters the multiplexed signals and in turn passes the filtered signals to a separate analog to digital converters. The analog to digital converters digitize the filtered signals and output these digitized signals to the DSP module for further processing. The DSP module orchestrates the digitization or sampling rate of the analog to digital converters by selecting between one of two oscillators having different frequencies. The selected oscillator is used to clock the analog to digital converters for providing one of two output data rates.
Microcontroller Module
The microcontroller module includes a microcontroller which is a versatile one-chip integrated microprocessor and peripheral combination that supports a Graphical User Interface (GUI), communications, and a high-level real-time operating systems such as the Windows(copyright)CE operating system. The microcontroller will be discussed below in combination with the digital signal processing module, the communications module and the user input and display module delineated below.
Digital Signal Processing Module
The digital signal processing module is comprised of a digital signal processor (DSP) that performs all of the signal processing necessary for the input transducers in use. Specifically, a shared memory device is interfaced between and shared by both the digital signal processor and the microprocessor. When first requiring the DSP to perform signal processing, the microcontroller places the DSP in reset, then downloads DSP code into the shared memory, and subsequently brings the DSP out of reset. This has the effect of forcing the DSP to load and run this code. Each download of DSP code to the shared memory can be, for example, different types of applications, different types of measurements, different types of transducers or any combination thereof for accommodating different types of sensed physical data for the large variety of different types of assets found in industrial plants.
Hence, one hallmark of the present invention is that downloading the code as and when required has the advantage that many different versions of DSP code can be used depending upon the application being run. In addition, this means that an EPROM is not needed to store code and rather, code can be upgraded by downloading new firmware to the portable data collector and analyzer apparatus. For example, if the present DSP code is reflective of vibration data collection and analyzes the future DSP code can be reflective of, for example, balancing, alignment, motor current or reciprocating compressor data collection and analyzes by downloading the code to the apparatus, as will be explained infra, and then employing the above method of placing the DSP in reset, downloading the desired DSP code into the shared memory and subsequently bringing the DSP out of reset for effecting the DSP to load and run this code. As a result, there is no need to change any of the hardware of the present invention to add new functionality for collecting and analyzing data a variety of different asset types.
Once the DSP code is run, the DSP receives configuration data describing which measurements to take. The DSP then orchestrates the digitization of the conditioned analog signals as delineated hereinabove, processes the digitized data and then writes out the results to the shared memory and informs the microcontroller that new results are available to be read.
The DSP is able to perform several processing tasks in parallel, depending upon what measurements are configured. For example, the DSP can perform a dual channel spectrum and also two channel overall vibration values as well as giving a speed measurement, all in parallel. Additionally, the DSP can calculate dual channel overall vibration, prime spike, rotor region, and gap values in parallel. Furthermore, the DSP can synchronously sample and calculate dual channel overall vibration, prime spike, rotor region, gap values and 1X and 2X vectors in parallel.
The DSP processing greatly benefits from a novel, useful and unobvious frequency shifting and decimation method for spectrum calculation.
Generally, the frequency shifting and decimation method according to the present invention includes the steps of:
(a) defining a resolution of lines of a final output line spectrum;
(b) selecting N digital data samples from the digitized data wherein N is an integer power of two (wherein the value of N is determined by the desired number of lines of resolution (N=2.56*lines of resolution);
(c) frequency shifting said N digital data samples by a predetermined frequency amount to produce a set of N point complex data,
(d) decimating said N point complex data for defining X number of decimated points wherein X is an integer,
(e) performing a Fast Fourier Transform on said X number of decimated points for producing a line spectrum;
(f) storing said line spectrum into memory, and
(g) iteratively repeating steps (c) through (f) for a predetermined integer number of times until said defined resolution of lines of the final output line spectrum is obtained.
The DSP processing also greatly benefits from a novel, useful and unobvious synchronous sampling method.
For background, the outputs of the analog to digital converters provide asynchronous data that can be placed into packets of data having a predetermined number of asynchronous samples contained therein. The DSP stores trigger pulse times in a buffer and once the predetermined number of samples have been received it processes this buffer. Hence, the synchronous sampling method according to the present invention includes the steps of:
(a) determining a start time of a packet of data having a predetermined number of asynchronous samples contained therein;
(b) determining a first trigger time which is later than the determined start time of the packet;
(c) determining a subsequent trigger time which is consecutive to the first trigger time and which is earlier than the determined end time of the packet;
(d) calculating a synchronous sample period by dividing the time between the consecutive trigger pulses by a predetermined synchronous sample rate;
(e) determining a first asynchronous sample that is prior to and closest the first trigger pulse and determining a second asynchronous sample consecutive to the first determined asynchronous sample;
(f) interpolating between the first and the second asynchronous samples for generating a value of a first synchronous sample at the first trigger pulse time,
(g) determining a subsequent synchronous sample time by adding the synchronous sample period to the first trigger pulse time,
(h) determining two asynchronous samples, one sample just before and one sample just after the subsequent synchronous sample time;
(i) interpolating between the two asynchronous samples for generating and storing a value of a subsequent synchronous sample at the subsequent synchronous sample time,
(j) determining a next subsequent synchronous sample time by adding the synchronous sample period to the last subsequent synchronous sample time,
(k) skipping to step (o) if the next subsequent synchronous sample time is after the time of the next trigger pulse;
(l) determining two asynchronous samples, one sample just before and one sample just after the next subsequent synchronous sample time;
(m) interpolating between the two asynchronous samples for generating a value for a next subsequent synchronous sample at the next subsequent synchronous sample time;
(n) iteratively repeating steps (j) through (m);
(o) iteratively repeating steps (j) through (m) if the time of the next trigger pulse is before the end of the asynchronous buffer and replacing the step (k) next trigger pulse value with a next trigger pulse value consecutive to the next trigger pulse value in step (k);
(p) storing the generated synchronous samples as a synchronous sample waveform if the next trigger pulse value in step (k) is after the end of the asynchronous buffer.
Subsequent buffers of asynchronous samples are processed using the above method and by simply replacing the buffer start time with a next subsequent synchronous sample time that is after the last subsequent synchronous sample time used to generate the last synchronous sample of the last synchronous sample waveform generated from the last buffer.
User Input and Display Module
The user input and display module is comprised of a clear touch screen, a quarter VGA display, and an ergonomically designed keypad which provide simple operation by a user with either the left or right hand, even with gloves on. The VGA display is backlit to provide excellent display viewing over a broad range of lighting conditions.
Thus, the clear touch screen overlying the quarter VGA display, the ergonomically designed programmable keypad, and an intuitive user interface allow quick and easy setup for in-field data acquisition and display.
Communications Module
The communications module is comprised of an Ethernet communications link and a serial communications link. These communications links are used to download information such as plant asset routes and application programs to the portable data collector and analyzer apparatus from a host computer. Data transfer is effected by merely coupling a cable between either of the communications links and the host computer. Hence, the present invention is void of a mode switch or similar device as is found in the prior art. Thus, the present invention solves the problem of the user inadvertently forgetting to actuate the mode switch and then leaving the apparatus unattended only to come back to an apparatus that has not effected the asset route download and thus, is not ready for field data acquisition. This delay increases the time spent on collecting data rather then correcting problems. Hence, the present invention provides improvement in speed that directly correlates to cost savings and problem correction.
Once one or more routes are downloaded from the host computer the user simply selects a desired route. The assets of the user selected route are then displayed on the display in a hierarchical manner and also measurements points associated with each selected asset are also displayed on the display in a hierarchical manner for guiding the user through the data collection process. At any time a measurement point may be skipped or additional measurement points not in the route may be added thereto.
After selection of a measurement point, transducer(s) are attached to the asset, such as a machine, and the user initiates the measurement cycle by pressing the appropriate button on the keypad of touching an appropriate on the touchscreen. The portable data collector and analyzer apparatus acquires all the measurement data and this data is automatically saved to memory without requiring any key actuation by the user thereby eliminating this extra time consuming step and eliminating the problem of the user inadvertently forgetting to save the collected measurement data before moving on to the next measurement point. Hence, the present invention is void of the limitation which requires key actuation to cause data to be transferred into memory. After the present invention automatically saves the collected measurement data from the measurement point to memory the user is prompted to the next measurement point.
The Ethernet communications link and the serial communications link also allow easy connection of accessories or peripherals. Furthermore, the present invention includes general purpose ports such as a PCMCIA card slot and keyboard interface that also allow easy connection of accessories or peripherals. For example, the PCMCIA card slot can be used for suitable alignment hardware controlled by software loaded as above.
Power Supply/Charger Module
The power supply/charger module is comprised of a 5 volt power supply, a PCMCIA power supply, a 3.3 volt power supply and a negative 24 volt power supply for meeting the power supply requirements of the portable data collector and analyzer apparatus. Preferably, the power for these supplies is provided by a single re-chargeable Lithium-Ion battery pack fitted inside the housing of the portable data collector and analyzer apparatus. The power supply and charger module also includes a battery charger circuit that couples to a commercially available 15V ac-dc adapter for charging the battery without removing it from the housing.
Accordingly, a primary object of the present invention is to provide a new, novel, and useful portable data collector and analyzer apparatus and method for collecting and analyzing industrial plant asset data for protecting and managing industrial plant assets including machinery.
A further object of the present invention is to provide a single multi-purpose apparatus and method that permits the preventative and predictive maintenance of a variety of assets typically found within an industrial complex.
Another further object of the present invention is to provide a single multi-purpose portable data collector and analyzer apparatus and method that can collect and analyze a variety of different types of asset data in a variety of different ways.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes an interface for constant current powered transducers such acceleration and velocity transducers, and which also includes an interface for general purpose signal inputs, including displacement, velocity, acceleration, temperature, pressure and other process variables transducers.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes an interface for Auto-Point ID devices.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes an interface for phase reference input from single output devices, such as displacement transducers, optical phase references transducers or magnetic pickup transducers, or from dual output devices, such as encoder transducers.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes a shared memory device interfaced between and shared by both a digital signal processor and a microprocessor for allowing the microprocessor, which is coupled to DSP, to place the DSP in reset and then download DSP code into the shared memory and subsequently bring the DSP out of reset for effecting the DSP to load and run this code thereby precluding the need of an EPROM which heretofore was required to store this code.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which can receive a download of DSP code from a host computer and then employ the above method of placing the DSP in reset, downloading the desired DSP code into the shared memory and subsequently bringing the DSP out of reset for effecting the DSP to load and run this code for adding new functionality to the present invention for collecting and analyzing data of a variety of different asset types with a variety of different measurements and transducers without requiring any type of hardware change of the present invention.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes a novel, useful and unobvious frequency shifting and decimation method for spectrum calculation that, inter alia, retains the efficient addressing of the DSP and thus increasing the signal processing speed of the present invention.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes a novel, useful and unobvious synchronous sampling method that generates synchronous sample waveforms from asynchronous sample waveforms.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes a clear touch screen overlying a quarter VGA display, an ergonomically designed keypad, and an intuitive user interface for allowing quick and easy setup for in-field data acquisition, analysis and display.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes inspection point and manually keyed in notes and observations.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes communications links for downloading information such as plant asset routes and application programs to the portable data collector and analyzer apparatus from a host computer which is effected by merely coupling a cable between either of the communications links and the host computer.
Another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes general purpose ports such as a PCMCIA card slot and keyboard interface that allow easy connection of accessories or peripherals
Yet another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes a variety of power supplies that are powered by a single re-chargeable battery pack fitted inside the housing of the portable data collector and analyzer apparatus.
Still yet another further object of the present invention is to provide a portable data collector and analyzer apparatus and method as characterized above which includes an on board battery charger circuit that couples to a commercially available 15V ac-dc adapter for charging the battery without removing it from the housing.
These and other objects and advantages will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures.